1. Technical Field
The present invention relates to aircraft electronics, and more particularly to a flight control module with integrated spoiler actuator electronics.
2. Background Information
Referring to FIG. 1, a typical airplane includes fuselage 110, which holds the passengers and the cargo; wings 112, which provide the lift needed to fly the airplane; vertical stabilizers 114 and horizontal stabilizers 116, which are used to ensure a stable flight; and engines 118, which provide the thrust needed to propel the airplane forward.
To guide an airplane, one must rely on flight control surfaces that are placed on wings 112, vertical stabilizers 114, and horizontal stabilizers 116. The primary flight control surfaces on an airplane include the ailerons 100, the elevators 102, and the rudder 104. Ailerons 100 are located on the trailing edges of the wings of the airplane and control the roll of the airplane. Rolling of an airplane is depicted in FIG. 2A. Elevators 102 are located on the horizontal stabilizer of an airplane and control the pitch of the airplane. Pitching of an airplane is depicted in FIG. 2B. Rudder 104 is located on the vertical stabilizer and controls the yaw of the airplane. Yawing of an airplane is illustrated in FIG. 2C.
Also present on the wings of an airplane are spoilers 106, flaps 120, and slats 122, collectively known as secondary flight control surfaces. Spoilers 106 are located on the wings and perform a variety of different functions, including assisting in the control of vertical flight path, acting as air brakes to control the forward speed of the airplane, and acting as ground spoilers to reduce wing lift to help maintain contact between the landing gear and the runway when braking.
Flaps 120 and slats 122 are located on the wings of an airplane to change the lift and drag forces effecting an airplane, with flaps 120 at the trailing edge of wing 112 and slats 122 at the leading edge wing 112. When flaps 120 and slats 122 are extended, the shape of the wing changes to provide more lift. With an increased lift, the airplane is able to fly at lower speeds, thus simplifying both the landing procedure and the take-off procedure.
The primary flight control surfaces described above are operated by a pilot located in the cockpit of the airplane. Rudder 104 is typically controlled by a pair of rudder pedals operated by the pilot""s feet. Ailerons 100 are controlled by adjusting a control stick to the left or right. Moving the control stick to the left typically controls the left aileron to rise and the right aileron to go down, causing the airplane to roll to the left. Elevator 102 is controlled by adjusting a control stick to the front or back. Spoilers 106 are typically operated by a separate control stick.
In most smaller airplanes, there is a direct mechanical linkage between the pilot""s controls and the moveable surfaces. In most larger airplanes, there may be cables or wires connecting the pilot""s controls to the hydraulic actuators used to move the primary control surfaces. In newer planes, a system called xe2x80x9cfly-by-wirexe2x80x9d has been developed.
In a typical, prior art, fly-by-wire airplane, electronic sensors are attached to the pilot""s controls. These sensors transmit electronic data to various flight control computers (xe2x80x9cFCCxe2x80x9d). A system known as the actuator control electronics (xe2x80x9cACExe2x80x9d) receives the electronic signals from the flight control computer and move hydraulic actuators based on the received signals. Each hydraulic actuator is coupled to a moveable surface such that movement of the actuator moves the primary control surface.
The fly-by-wire concept results in a savings of weight as there is no longer a need for heavy linkages, cables, pulleys, and brackets running throughout the airplane to control the actuators, only electrical wiring to the FCC and the ACE. Furthermore, this concept may result in a smoother flight, with less effort needed by the pilot.
Although fly-by-wire systems have proven to be very reliable in the past a secondary backup system may be desirable. In the prior art, a mechanical backup has been used. For example, the Boeing 777 airplane uses a cable-driven spoiler on each wing and a hydraulically controlled trim system on the horizontal stabilizer to control the airplane in the event of a failure of the primary flight control surfaces. The present invention eliminates the need for a mechanical backup.
The following summary of the invention is provided to facilitate an understanding of some of the innovative features unique to the present invention, and is not intended to be a full description. A full appreciation of the various aspects of the invention can only be gained by taking the entire specification, claims, drawings, and abstract as a whole.
The present invention concerns a spoiler actuator control electronics unit (xe2x80x9cspoiler ACExe2x80x9d) located within a flight control module. In one embodiment of the invention, the spoiler ACE is electrically separate from the Flight Control Module (xe2x80x9cFCMxe2x80x9d), having an independent power supply and separate input and output ports. The spoiler ACE receives input from a pilot""s control stick and translates the input into electrical signals that control the movements of hydraulic actuators which move the spoilers.
The spoiler ACE also can have a mode of operation in which augmentation signals are transmitted by the FCM. These augmentation signals can be limited by limiters and interlocks such that the FCM does not transmit potentially dangerous signals to the hydraulic actuators.
The novel features of the present invention will become apparent to those of skill in the art upon examination of the following detailed description of the invention or can be learned by practice of the present invention. It should be understood, however, that the detailed description of the invention and the specific examples presented, while indicating certain embodiments of the present invention, are provided for illustration purposes only, because various changes and modifications within the spirit and scope of the invention will become apparent to those of skill in the art from the detailed description of the invention and claims that follow.